And charles h



(Model.) Y,

S. BURTON 8v C. H. WILLCOX.

EEED MEGHANISM EOE SEWING MACHINES.

No. 255,577 Patented Max. 28,1882.

y UNITED STATES PATENT OFFICE.

STOOKTON BURTON, OF PHILADELPHIA, PENNSYLVANIA, AND UHARLES H.. WILLCOX,OF NEW YORK, N. Y., ASSIGNORS TO THE WILLCOX & GIBBS SEWING MACHINECOMPANY, -OF NEWr YORK, N. Y.

FEED MECHANISM FOR SEWING-MACHINES.

SPECIFICATION forming part of Letters Patent No. 255,577, dated March28, 1882.

Application filed December 28, 1881. (Model.)

and State of Pennsylvania, and CHARLES H.

WILLCOX, of New York city, in the county and State of New York, haveinvented a. new and useful Improvement in Feed Mechanisms forSewing-lvlachines, which improvement is fully set forth in the followingspecification.

This invention has reference more particularly to machines for sewingknit goods; and ithas for its object to enable a manufacturer to controlthe size of stitches in the work made by his operatives.

In the manufacture of this class ot' goods it was for a long timecustomary to use a very longstitch, and the tendency on the part oftheoperatives is to continue the use of the long stitch, partly fromhabit and partly in zo order to get over the work more rapidly. It

has, however, been found advantageous to materially reduce the length'ot' stitch, the best work being done when the length of stitch equalsthe gage of the fabric-that is, the dis- 2 5 tance between the centersof adjacent loops or half the distance between the needles on which thefabric has been knit. It is therefore very desirablcto provideameanswhereby the stitch made by machines in the hands of the. opera- 3o tivescan be controlled.

To this end the present invention consists in combining with the cam orother device whereby the movement of the feed-bar, and consequentlythelength of stitch, is regulated, alocking device, so that when thesaid feed-regulating cam has been set to give the proper length ofstitch it cannot be altered, except by the foreman or person having themachine under control.

4o The accompanying drawings, which form a part of this specification,illustrate an apparatas constructed in accordance with the invention,Figure l being a side elevation; Fig. 2, an end view; and Fig. 3, avertical section,

.45 partly in elevation.

A is the feed-regulating cam, B a clampingplate, and C a lockingscrew-bolt. The feed mechanism shown, the movement of which is regulatedby the cam A, is that in common use on the Willcox 85 Gibbs chain-stitchma.- 5o chine, and needs no description.

The clamping-plate B is `supported on the same pin, D, with thefeed-regulating cam A.

A spring-washer, E, is preferably placed between the head of the pin Dand the clampingplate, so as to press the latter against the feedcam.The feed-cam is provided with a curved slot, F. The lockingscrcw-bolt Ititsin a hole in the machine-frame G, passes through the slot F in thefeed-cam, and is tapped into the 6o clamping-plate. The head of thisbolt isso formed as to require a special key for turning. As shown, ithas a projection or extension, a, in the center, and at the base thereofan annular collar, b, in which are notches c; and the special key H,Fig. 3, is formed with a hollow in its end to receive the said extensionor projection c and prongs to fit in the notches c. When thelocking-boltis released the feed-cam Acan be turned to make the desiredlength of 7o stitch, the slot 'F allowing the requisite movemeut to bemade. When properly adjusted the locking-bolt is turned by the specialkey, and the feed-cam is securely held between the machine-frame andclamping-plate until again released by turning the locking-bolt I.

The hinged shield K (shown in Fig. l) is adapted to cover the looper andfeed mechanism during the operation of the machine, and to be swung downto expose these parts when 8o this is desired for any reason.

Although the means described are deelne the best for the purpose, theinvention is not limited thereto, as it is obvious that modifications.may be made Without altering the general principle of the device.

The invention is applicable to all kinds of sewingmachines, to thoseusing a top feed as Well as to those in which the feed is beneath thecloth-plate, and to those using other feed- 9o regulating devices aswell as to those employing a feed-cam.

The locking-feed mechanism, instead of being applied to thefeed-regulator directly, could 'be otherwise applied, so as to protectthe feed movement from alteration, except by means of the special key ordevice for that purpose.

We claim- 1. The combination, with the feed-regulator of asewing-machine, of a locking device for preventing alteration of thefeed by the operator, substantially as described.

2. The combination ofa feed-regulator, clampin g-plate, andlocking-bolt, substantially as described.

3. A locking screw-bolt, in combination with a slotted feed-regulatingcam and clampingplate, substantially as described.

4. The combination ofthe slotted feed-regulating cam7 itssupporting-pin, the clampingplate, the spring-washer, and thelocking-bolt, substantially as described.

5. The combination, with the adjustable feed cfa. sewing-machine,oflocking mechanism for zo STOCKTON BORTON. CHAS. H. WILLGOX.

Witnesses:

JOHN G. PURKIs, GILMAN E. J OPP.

